Endoscopic viewing devices are well known in the art. In general, such devices are used to view the interior of limited access spaces such as body cavities, the interiors of complex machinery, etc. Endoscopic viewing devices generally comprise an elongated shaft having a distal end and a proximal end, and at least one internal passageway extending between the distal end and the proximal end. The shaft may be rigid or flexible, depending on the particular application involved. Image capturing means extend through the shaft's at least one internal passageway and are adapted to capture an image of a selected region located substantially adjacent to the distal end of the shaft, and to convey that image to a viewing device disposed at the proximal end of the shaft. In order to assist viewing, illumination means are also typically provided on the endoscope. The illumination means also extend through the shaft's at least one internal passageway and are adapted to project light onto the region to be viewed by the image capturing means.
The image capturing means commonly utilize one of several different arrangements to capture an image at the distal end of the shaft and to convey it to a viewing device located at the proximal end of the shaft.
In one arrangement, the image capturing means comprise a bundle of fiber optic filaments extending through the shaft's at least one internal passageway. An appropriate lens is positioned at the distal end of the shaft to focus the desired image onto the distal end of the fiber optic bundle. A conventional optical viewer or eyepiece is positioned at the proximal end of the shaft to receive the image conveyed to the proximal end of the fiber optic bundle. Alternatively, an appropriate image sensor, such as a charge coupled device ("CCD") element or video tube, may be positioned at the proximal end of the shaft to receive the image conveyed to the proximal end of the fiber optic bundle. Wires then connect the image sensor to an adjacent viewing device.
In a second arrangement, the image capturing means comprise a CCD element disposed at the distal end of the shaft. An appropriate lens focuses the desired image onto the CCD element's light-receiving surface, and wires extend through the shaft's at least one internal passageway to connect the endoscope's CCD element to a viewing device located adjacent to the proximal end of the shaft.
In a third arrangement, the image capturing means comprise a so-called rod-lens system. In this embodiment, a series of rod lens elements are arranged within the shaft's at least one internal passageway so as to capture the desired image at the distal end of the shaft and convey it to the proximal end of the shaft. A conventional optical viewer or eyepiece is positioned at the proximal end of the shaft to receive the image which is conveyed to the proximal end of the rod-lens system. Alternatively, an appropriate image sensor, such as a charge coupled device ("CCD") element or video tube, may be positioned at the proximal end of the shaft to receive the image conveyed to the proximal end of the rod-lens system. Wires then connect the image sensor to an adjacent viewing device.
The illumination means commonly comprise apparatus for conveying light from a light source disposed at the proximal end of the shaft to an exit point located at the distal end of the shaft. For example, the illumination means frequently comprise a bundle of fiber optic filaments extending through the shaft's at least one internal passageway.
In practice, endoscopic viewing devices have taken on several common forms. More specifically, endoscopic viewing devices have been designed such that either (i) the image capturing means open onto the distal end of the shaft so as to face distally therefrom; (ii) the image capturing means open onto the distal end of the shaft so as to face outwardly therefrom at fixed or movable oblique angles; (iii) the image capturing means are disposed relative to the distal end of the shaft as set forth in categories (i) or (ii) above and the distal end of the shaft is itself deflectable relative to its longitudinal axis (i.e., the shaft is "steerable"); (iv) the image capturing means open onto the side wall of the shaft substantially adjacent to its distal end surface; or (v) the distal end of the shaft is affixed to a surgical instrument substantially adjacent to the working end of the surgical instrument. Examples of endoscopes exhibiting the characteristics of the aforementioned category (i) are shown in the following U.S. patents:
______________________________________ U.S. Pat. No. Issued To ______________________________________ 1,345,406 7/6/20 Rimmer 3,581,738 6/1/71 Moore 4,245,624 1/20/81 Komiya 4,419,987 12/13/83 Ogiu 4,445,892 5/1/84 Hussein et al. 4,461,283 7/24/84 Doi 4,606,330 8/19/86 Bonnet 4,617,915 10/21/86 Arakawa 4,641,912 2/10/87 Goldenberg 4,662,368 5/5/87 Hussein et al. 4,672,963 6/16/87 Barken 4,718,406 1/12/88 Bregman et al. 4,740,047 4/26/88 Abe et al. 4,770,653 9/13/88 Shturman 4,788,975 12/6/88 Shturman et al. 4,798,193 1/17/89 Giesy et al. 4,874,371 10/17/89 Comben et al. 4,887,600 12/19/89 Watson et al. 4,899,733 2/13/90 DeCastro et al. ______________________________________
Still another example of an endoscope exhibiting the characteristics of the aforementioned category (i) is shown in Soviet Union Patent Document No. SU 1020-124-A dated Mar. 27, 1981.
All of the foregoing patents are incorporated herein by reference.
Examples of endoscopes exhibiting the characteristics of the aforementioned category (ii) are shown in the following U.S. patents:
______________________________________ U.S. Pat. No. Issued To ______________________________________ 4,175,545 11/27/79 Termanini 4,418,688 12/6/83 Loeb 4,784,132 11/15/88 Fox et al. 4,800,876 1/31/89 Fox et al. 5,127,393 7/7/92 McFarlin et al. ______________________________________
All of the foregoing patents are also incorporated herein by reference.
Examples of endoscopes exhibiting the characteristics of the aforementioned category (iii) are shown in the following U.S. patents:
______________________________________ U.S. Pat. No. Issued To ______________________________________ 3,886,933 6/3/75 Mori et al. 4,648,892 3/10/87 Kittrell et al. 4,669,467 6/2/87 Willett et al. 4,911,148 3/27/90 Sosnowski et al. 4,996,974 3/5/91 Clariei 5,083,549 1/28/92 Cho et al. ______________________________________
All of the foregoing patents are also incorporated herein by reference.
Examples of endoscopes exhibiting the characteristics of the aforementioned category (iv) are shown in the following U.S. patents:
______________________________________ U.S. Pat. No. Issued To ______________________________________ 4,277,168 7/7/81 Oku 4,375,818 3/8/83 Suwaki et al. 4,699,463 10/13/87 D'Amelio et al. 4,905,667 3/6/90 Foerster et al. ______________________________________
More particularly, the Oku patent shows a side view endoscope which is designed to be rotated about its longitudinal axis by a pair of parallel, rigid wires which extend through the endoscope's shaft and are affixed to the distal end of the shaft. A first bundle of fiber optic filaments (i.e., the illumination means) conveys light from a light source located adjacent to the proximal end of the shaft to a first opening formed in the side wall of the shaft adjacent to its distal end surface. A second bundle of fiber optic filaments (i.e., the image capturing means) gathers an image from a mirror and lens arrangement disposed at a second opening located in the side wall of the shaft adjacent to the first opening, and conveys the same to a viewing device located at the proximal end of the shaft. The rotational position of the shaft is tracked relative to an outer sheath by third and fourth bundles of fiber optic filaments, which extend from the proximal end of the shaft to a third opening formed in the side wall of the shaft. The third opening is spaced proximally from the first and second openings and faces the interior of the outer sheath. The third bundle of fiber optic filaments is used to illuminate the portion of the outer sheath located adjacent to the shaft's third opening, and the fourth bundle of fiber optic filaments is used to view the portion of the outer sheath located adjacent to the shaft's third opening. Using the third and fourth bundles of fiber optic filaments, the operator can monitor rotation of the shaft's third opening past graduated markings on the inner surface of the outer sheath, etc. so as to determine the rotational position of the shaft relative to the outer sheath.
The Suwaki et al. patent shows a side view endoscope including an ultrasonic diagnosis system. With this endoscope, side viewing is provided by means similar to those provided by the Oku patent, i.e., a first bundle of fiber optic filaments (i.e., the illumination means) projects light out of a first opening in the shaft, and a second bundle of fiber optic filaments (i.e., the image capturing means) gathers an image from a mirror and lens arrangement disposed at a second opening in the shaft and conveys the same to the proximal end of the shaft. In addition, a third opening is provided in the side wall of the endoscope in adjacent, axially-spaced relation to the first and second openings. An ultrasonic wave generator is adapted to emit ultrasonic waves out of the shaft's third opening and against adjacent tissue as that tissue is illuminated and viewed by the first and second bundles of fiber optic filaments, respectively.
The D'Amelio patent shows an endoscope of the type exhibiting the characteristics of the aforementioned category (i), i.e., an endoscope adapted for distally directed viewing. In addition, however, a cap member is also provided at the distal end of the shaft. This cap member is rotatable relative to the shaft and contains both an axially directed passageway and a generally L-shaped passageway having a mirror disposed at the inside corner of the "L". As a result of this construction, when the cap is turned so that its axial passageway is aligned with the endoscope's viewing system, the device allows an axially positioned field to be viewed. At the same time, when the cap is turned so that its L-shaped passageway is aligned with the endoscope's viewing system, the device allows a radially positioned field to be viewed.
The Foerster et al. patent discloses a side view duodenoscope, but does not specifically disclose the means by which the side viewing capability of the scope is provided.
All of the foregoing patents are also incorporated herein by reference.
Finally, an example of an endoscope exhibiting the characteristics of the aforementioned category (v) is shown in U.S. Pat. No. 4,759,348 issued Jul. 26, 1988 to Cawood.
This patent is also incorporated herein by reference.
In view of the foregoing, it will be appreciated that some endoscopic viewing systems currently exist which permit the operator to view fields located in axial alignment with the distal end of the shaft, while other endoscopic viewing systems currently exist which permit the operator to view fields located at various angles to the longitudinal axis of the endoscope.
In addition to the foregoing, endoscopic viewing devices have also been developed for stereoscopically viewing objects located in axial alignment with the distal end of the endoscope. These devices generally utilize a pair of viewing systems like those discussed above with respect to the aforementioned category (i) devices, but with the two viewing systems arranged so as to have the same or largely overlapping fields of view. The images from each of the two viewing systems are combined in the endoscope's display so as to provide the operator with a stereoscopic view of any objects and/or structures located within the common viewing field.
Unfortunately, none of the foregoing endoscopic viewing systems is entirely satisfactory.
More particularly, it should be appreciated that the field of view for all of the foregoing endoscopic viewing devices is generally quite limited in scope, relative to the size of the anatomy or region which is typically under examination. Fortunately, in many situations the operator can compensate for this simply by moving the endoscope about the surgical site or other volume of interest. For example, the operator may move the entire endoscope proximally or distally, or the operator may rotate the scope about its longitudinal axis, or the operator may combine these two actions. It has been found in many applications that by moving the endoscope about in this way, substantially the entire surgical site can be viewed through the endoscope.
In some situations such as those where the primary goal of a procedure is visual examination, the foregoing capabilities may be adequate. In other situations such as laparoscopic surgical procedures, however, it is generally difficult for the surgeon to simultaneously manipulate both the surgical instruments needed to perform the surgical procedure and the endoscope needed to view the procedure. As a result, another person must generally assist the surgeon by manipulating either one or more of the surgical instruments and/or the endoscope in coordination with the surgeon.
The device discussed above with respect to the aforementioned category (v) attempts to alleviate this problem by attaching the viewing head of the endoscope directly onto the working end of the surgical instrument. Unfortunately, however, this arrangement is not totally satisfactory. For one thing, it does not provide the surgeon with a view of any objects and/or structures which may be somewhat removed from the working end of the surgical instrument, nor does it permit the surgeon to have a "bird's eye" (or "third person") view of the surgical instrument while that instrument is being used in surgery.
Furthermore, in many applications it may be difficult or even impossible to move the endoscope about the surgical site so as to compensate for the endoscope's limited field of view. For example, the surgical site might be a highly confined region or include hard to reach locations. Also, the surgical site might be surrounded by delicate tissue such that endoscope movement should be minimized.
Accordingly, an improved endoscopic viewing system is needed which can provide "on command" images of one or more fields of view surrounding the distal end of the endoscope, without the need for any physical manipulation of the endoscope whatsoever from an initially established position. The provision of such a device would minimize or eliminate the need to move the endoscope about the surgical site during a procedure, while still providing the surgeon with an excellent view of the entire surgical site and any objects and/or structures located in the vicinity of the surgical site.